(function () {
    var bar={
        myName:"time",
        printName:function () {
            console.log(myName);
        }
    }
    function foo(){
        let myName="极客时间";
        return bar.printName;
    }

    let myName="极客邦";
    let _printName=foo();
    _printName();
    bar.printName();
})()